Yesterday on Pop Pilgrims, we asked where else people go to recreate famous movie scenes. Nothing will likely rival the nearly continuous stream of people who retrace Sylvester Stallone’s footsteps up the stairs in front of the Philadelphia Museum Of Art, but just outside of Philly, one cinematic landmark ratchets up the spectacle.

Each year, several hundred people race out of Phoenixville’s Colonial Theater to recreate a scene from the landmark 1958 horror film The Blob. It’s all part of the annual Blobfest, a celebration of The Blob and the pivotal role the Colonial plays in Irvin “Shorty” Yeaworth’s film. (This year’s event takes place this weekend, July 8-10.)

It’s in the theater’s projection booth that the titular Blob escalates its attack. It seeps through the ventilation duct, takes out the projectionist, then oozes through the projection-room windows and into the theater. Moviegoers checking out Daughter Of Horror (a.k.a. Dementia) flee the theater in a panic, running into the street and tripping over each other. The Blobfest re-enactment, called The Run Out, is one of the fest’s most popular events—this year’s event sold out long ago—and the city even sets up bleachers outside the theater for people to watch the shenanigans. While The A.V. Club shot outside the theater, a family came up and did their own run out.

As Blobfest indicates, the Colonial celebrates its association to the movie. A plaque at the back of its balcony commemorates the projection-room scene, and visitors are advised to rub the bulging Blob on it for good luck. Blobfest also features a scream contest, film competition, street festival, and, of course, multiple screenings of The Blob.

Is it that good of a movie? No. Fifty-plus years later, it’s pretty kitschy, but it’s better than the 1988 remake (shot in Louisiana) starring Johnny Drama. Not only was The Blob the first big role for actor Steve McQueen, but it also featured some innovative special effects for the time. “They would take a glob of the goo, heat it up, and then tilt it with the camera so it would look like it’s moving,” says Shane Stone (a.k.a. Dr. Frank N. Stone), Blobfest organizer. “So that was pretty high-tech for then, to make this goo actually move.”

The Blob also bucked the creature-feature tradition. There were werewolves, vampires, creatures from a Black Lagoon, etc., but Yeaworth’s monster was a creeping, amorphous mass. Even five decades later, that’s a bold choice. Yeaworth didn’t come from a traditional Hollywood background. He didn’t even come from Hollywood. He was a local whose previous experience was with religious and instructional films, and he would return to those not long after The Blob, which he financed himself.

The actual Blob lives on to this day—in a bucket. Yeaworth shot the Blob action on miniature sets, so the Blob itself—silicone gel dyed red—is actually pretty small. A private collector owns it, but brings it out for Blobfest, where it receives an enthusiastic homecoming.

The Philadelphia Museum Of Art has its statue, the Colonial Theater has its bucket o’ goo. The Philly area runs the gamut when it comes to pop-culture landmarks.